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An Optical Bit-Counting AlgorithmThis paper addresses the omnipresent problem of counting bits - an operation discussed since the very early stages of the establishing of computer science. The need for a quick bit-counting method acquires a special significance with the proliferation of search engines on the Internet. It arises in several other computer applications. This is especially true in information retrieval in which an array of binary vectors is used to represent a characteristic function (CF) of a set of qualified documents. The number of "I"s in the CF equals the cardinality of the set. The process of repeated evaluations of this cardinality is a pivotal point in choosing a rational strategy for deciding whether to constrain or broaden the search criteria to ensure selection of the desired items. Another need for bit-counting occurs when trying to determine the differences between given files, (images or text), in terms of the Hamming distance. An Exclusive OR operation applied to a pair of files results in a binary vector array of mismatches that must be counted.
Document ID
20000038731
Acquisition Source
Goddard Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Mack, Marilyn
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Lapir, Gennadi M.
(ZERES Bochum Germany)
Berkovich, Simon
(George Washington Univ. Washington, DC United States)
Date Acquired
September 7, 2013
Publication Date
January 1, 2000
Subject Category
Cybernetics, Artificial Intelligence And Robotics
Meeting Information
Meeting: JCIS 2000
Location: Atlantic City, NJ
Country: United States
Start Date: January 1, 2000
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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